Fountain pen



May 13, 1941 L. P. MARTJN AErm. 2,241,865

'FOUNTAIN PEN Filed Deo. 28, 1939 zz la' 3 fluid to the fissures.

the hand in holding the fountain pen for writing l point end of the pen nib.

Patented May 13, 1941 UNITED sTATl-:s

PATENT OFFICE FoUN'ralN PEN Delawarel Application December 28, 1939, Serial No. 311,352

having a ssure therethrough on the pen nib sup-v porting surface thereof and the core having a filssure on the periphery thereof communicating with the reservoir and with the shell fissure for directing iiuid from the reservoir to the pen nib. The core is provided with capillary chambers and an aperture communicating therewith and with the atmosphere.A Also, -an air pass'age is pro- .vided in the core communicating at one end thereof with the reservoir and at theother end thereof. with a Acapillary sealing channel in the core, the sealing channel having communication with the ssures of the shell and core and therethrough with the capillary chambers whereby the air passage is sealed when more than a normal amount of uid is supplied to the flssures for writing, and air' is admitted to the air passage when the sealingchannel is` exhaustedto replace iiuid in the reservoir for the normal supply of l In the ordinary use of a fountain pen, writing /3 fluid is fed. by capillary attraction from theslit in the -pen nib onto a writing surface. The iiuid of a reservoir of a fountain pen is fed to the slit of the pen nib thereof through channels in the feed section, the slit andchannels being of capil' 35 lary dimensions. Ordinarily, the channelspermit a supply of writing fluid to the writing surface in just sufficient quantity for normal use. Howevenduri'ng such conditions as, for example, when the reservoir of the fountain pen is par-v 40 tially exhausted of writingY fiuidfther-heat from will expand the air behindthe remaining fluid and force through the channels an excess of the amount necessary for ordinary writing. In order to compensate for the excess supply of writing fluid fed to the pen nib it is usual to provide the feed section with storage chambers in communication with 4the feed ,ducts to relieve the feed ducts'of the excess supply of writing-fluid. The 50 storage chambersl are ordinarily of capillary dimensions and the attraction thereof for the writing uid is greater than the action of gravity and prevents the uid from dropping off the writing -The present invention has for an object the provision of storage or expansion chambers in a feed for a fountain pen, the capacity of which is so great that only under the mosttunusual conditions not contemplated in normal use might suiiicient expansion occur within the reservoir to force fluid to drop from the pen nib. Under all conditions to which the fountain pen is subjected in normal use the present invention contemplates provision for the storage of any excess amount of fluid forced by expansion from the fluid reservoir. Tests have proven that the present construction will control excess fiuid from expansion caused by a temperature change.

Another object of this invention is to provide a separation of the fluid and air ducts inorder that a more uniform flow of fluid may be had from the reservoir to the pen nib. In the following description it will be pointed out that a separate and definite path for fluid to flow from the fluid reservoir tothe pen nib and for air to take the place of, the uid in the reservoir ishad by new and novel structure. The path for the air supply to the reservoir'is sealed when more than a sufdcient amount of fiuid is had in the feeding means for normal use in writing and the path is opened to permit a supply of fluid to flow from the reservoir to the feeding means when the seal is broken. No air is permitted to take the place of the writing fluid in the reservoir, for example, when writing fiuid is present in the capillary chambers. Not until the fluidin the expansion chambers has been evacuated -and lthe fluid `forming the vseal between the feed duct and air duct is in use will air be permitted to enter the reservoir. One of the advantages of separat- -ing the uid and air ducts is to eliminate the pulsating effect socommonly found in fountain pens when the Iair passing to the reservoir to take the place of fluid therefrom forms bubbles which normally interrupt thel continuous flow y of fluid from the reservoir to the pen nib.

The present invention alsocontemplates the provision of an air vent in communication between the atmosphere and the capillary chambers. The core is provided with an internal longitudinally extending passage extending from one end thereof to .a position near the lother end .4

-thereof adjacent the inner end of the series of capillary chambers or, in thel instance shown.

transversely extending comb cuts. The provision of .this airvent in such relation permits'- I the filling of the fountain pen merely by immersing the tip end of the feeding'm'eans. The

air vent permitsthe evacuation of air from the diretted upwardly.

I2 extending from the open end of the pen ventA also serves to augment the normal capacity of the chambers and the vent may 'be of capillary dimensionsif desired.

r'I'he capillary chambers or, as Vhas been illustrated in the drawing, the transversely extending comb cuts extend over a major portion of the peripheral surface of the case. A small number of comb cuts adjacent the reservoir end i of the core is disconnected from the major portion thereof by a laterally-extending peripheral channel of greater than capillary dimensions and the vent is in vcommunication with this channel. As both sets of comb cuts are of capillary dimensions Aand the channel therebetween is not of capillary dimensions, Writing fluid in excess of the amount necessary for normal writing would be accommodated in both sets of comb cuts before any fluid would be stored in the channel, -capillary attraction being great enough to overcome the force of gravity which would normally ll the channel. 'I'he smaller number of comb cuts also for the purpose of accommodating such expansion of writing uid as may occur when vthe fountain pen is carried in the pocket with the writing point of the pen An overflow into the vent would not occur in this condition until the small number of comb cuts are lled. Thus, in the writing condition and in the carried position,`

expansion of uid from the vreservoir of the,

fountain pen -is accommodated and there is no condition where expansion cannot be accommodated.

Other objects and advantages of this invention will hereinafter be more particularly pointed out and, for a morecomplete understanding of the characteristic features of this invention, reference may now be had to the following description when taken together with the accompany- '.ing drawing, in which latter:

Eigurel is a side elevational view partially section of a pen section for a fountain pen embodying the features of this invention, the pen holder being shown fragmentarily in section;

Fig. 2 is a plan elevational view of the pen section of Fig. 1;

Fig. 3 is a central longitudinal sectional view taken on the line 3-3 of Fig. 2

Fig. 4 is a longitudinal sectional view taken on the line 4--4 of Fig. 1, the peri holder and nib being omitted; Fig. 5 is a transverse sectional view 'taken onthe line 5-5 of Fig. 1; y

Fig. 6 is a transverse sectional view taken on the line'S--G of Fig. 1;

Fig. 7 is a.- perspective view of the core element Fig. 10 is a sectionalview taken on the line III-III of Fig. 9.

Referring now more particularly to the dra ing, the fountain pen embodying the features of this intention comprises a holder III having a.

writing uid reservoir II therein, a pen section holder in communication with the fluid reservoir thereof.

The pen section comprises anV outer shell Il having apen nib supporting surface or portion I4 on which a pen nib I5 rests. A fissure I6 is cut through the shell on the pen nib supporting surface and extends from a point adjacent the writing'point end of the shell toward the holder therefor preferably at least a sufficient distance to extend beyond the end of the slit in the pen nib I5.

A core fI1 preferably of circular cross section is housed within the shell I3, an intermediate portion of the core being of reduced cross section and being provided peripherally of the intermediate portion of reduced cross section with capillary chambers in the form of transversely extending comb cuts I8 of capillary dimensions.

The ends of the core are of relatively enlarged cross section and are of such a size and shape preferably to snugly engage the bore of the shell. While the periphery of the core II and the bore of the shell I3 which it engages are, as above stated, preferably circular, it is to be understood that'the configuration thereof may be changed Without departing from the spirit of this invention.

The co'mb cuts I8 of capillary dimensionare preferably of uniform size,'the`combs being separated into two series or sets A arid B by a transversely extendingA peripheral channel I9 of greater than capillary dimensions. All of the comb cuts communicate with a. fissure 20 extending longitudinally of the core for registration f with the ssure I6 and for communication between the iiuid reservoir II and thepen nib I5. 'I'he fissure 20 is narrow and of substantially smaller width than the widthv of the comb cuts I8 and thereby has a greater capillary attraction than the comb cuts. Fluid from the uid reservoir II is attracted along the fissure 20 and thereby to the fissure IiV at the forward e'nd thereof, with which the vssure 20 is in registration, to provide uidjo the slit of the pen nib 15. The slit if) the pen nib I5 is likewise 0f of the .pen section. shown .inv the preceding and keeps the iluivd from flowing outof the capillary dimensions, being very narrow, and feeds fluid to the writing surface.

Should an expansion occur in the fluid reser- I vvoir for any reason and the fluid forced into 'thelissure 2lbein excessoftheamountneeded for writing, such excess amountv is stored in the, comb cuts I 8 .which are of capillary dimension.v The attraction of the comb cuts isgreater than the action of gravity and, therefore, 'the comb -cuts are illled before the writing fluid will'drop from the end of the' pen nib. When all of the comb cuts Il'of the sets or series A and' B are lled, fluid will overflow through the passagell extending angularly of the longitudinal axis of the insert into an axially extending aperture 22. I'he surface tension of the wallsof the aperture 22 is also stronger than the forces of gravity aperture until thev extent -of the surface ofthe aperture is exhausted. The axial-aperture 22 communicates. therefore, with. the atmosphere at the writing point end of the pen section, the other end communicating through the passage 2| with the comb cuts I8 and with the fissures 2li and I8. Y'

In order that writing fluid be drawn from the" iiuid reservoir II to supply the pen nib in writing, it is necessary that air be admitted to the reservoir to take the place ofthe writing uid fluid reservoir I I.

between the air passage 23 and the remaining supplied therefrom. The fissure 20 which is the only means ofcommunication between the reservoir and the writing fluid feeding mechanism is of very small width and, were air topass in one direction through the fissure 20 to the reservoir to take the place of the fluid supplied to the fissure and therethrough to the Writing nib, a pulsating effect would be obtained owing vto the passage of the air bubble through the fissure .to the reservoir. The flow of fluid through the fissure 20 would be momentarily stopped until the bubble of air has passed therethrough.

The above mentioned pulsating effect lis not desirable in writing and it is, therefore, contemplated by this invention to provide a wholly independent path for the flow of the writing fluid. An air passage 23 is cut in the periphery of the core I1, the passage extending longitudinally from the juncturel of the reduced portion of the core at the writing point end thereof with the relatively enlarged portion thereof through to the opposite end for communication with the The only communication had fluid feeding portions of the pen section is provided vby a sealing means in the form of a capillary channel comprising an undercut 24 at the juncture of the relatively reduced and enlarged portions of the core at the writing point end thereof. The undercut or capillary channel 24 communicates with the fissures I6 and 20 and through the latter fissure with the comb cuts I8.

In the operation of the feeding mechanism of the pen section thus described the normal path of the fluid in writing is from the fluid reservoir I I through the fissure 20 to the fissure I6 of the shell. and to the slit of the pen nib lI5 resting on the supporting portion of the shell. Should expansion occur in the fluid reservoir and fluid pass through the fissure 20 'in excess of the amount needed for writing, such excess fluid is attracted first into the undercut 24 and thereafter into the comb cuts Il and, the attraction of the comb cuts being greater than the action of gravity, all of the. comb cuts are filled before writing fluid will 'drop from the point of the pen. If the amount of excess fluid is greater than the capacity of the comb cuts, su'ch excess will pass through the passage 2i into the axial aperture 22 and the surface tension of the walls of the passage and aperture is sufficient to overcome the force of gravity to keep the fluid from flowing out of the aperture until the extent of `the surfaces thereof is exhausted. However, after the peak of expansion has been reached, which ordinarily occurs long prior to the time that the comb cuts are completely filled, continued writing will gradually draw the fluid from the expansion chambers thus provided by the comb cuts and, when all of the comb cuts are empty, 'continued writing fluid wii1 be normally supplied through the fissure 2l.

During normal writing and after the fissures 20 and I6 are lled with fluid, the capillary channel 24, which is of smaller dimension than the comb cuts II, is supplied with fluid to form a liquid seal before fluid can be fed to the comb cuts Il. The fluid in the fissures I8 and'2l is never exhausted in normal writing and air is continuously fed to the reservoir through the pas- .sage 2l. 'I'he air supply is out oil' only when an excess amount of fluid. due to expansion or the like is present in the sealing channel or in both the sealing channel and comb. cuts whereafter the comb cuts are evacuated first and therenormal writing conditions and until expansion in the fluid reservoir again takes place. At no time when the comb cuts I8 are filled with anv excess supply of writing fluid will any air be permitted to pass through the air passage 23 and, thus, no writing fluid in the reservoir will be permitted to be drawn therefrom.

The air vent 22, besides its described use as an overflow duct, permits the exhaust of air from the comb cuts 4as they` are supplied `with the fluid in excess ofthe amount necessary in normal writing. This excess supply of fluid builds up from the writing point end of the feeding means when the fountain.` pen is held in position in writing. The overflow duct 2l communicating between the'channel I9 and the vent 22 is as above stated between the sets of capil-` lary chambers or cross cuts A and B. This is `desirable since there may be a condition, as

when carried with the writing point directed upwardly, when there is an expansion of fluid from the reservoir. If the overflow duct 2I were immediatelyadjacent the ends of the comb cuts and the reservoir was absolutely full, there would beI no accommodation for expansion and the fluid would be forced into the vent. In the present arrangement any expansion within normal limits will be accommodated. l

It may also be desirable to-aord -a capillary communication between the sets A and B of comb cuts and such means is shown in the form A of a flssure25 extending longitudinally on each side of the channel I9. The channel preferably intersects the overflow duct 2| and extends to the vent 22 for communication therewith. Further, a peripheral portion of the core is preferably cut away as at 26 and 21 on opposite sides of the, air passage 23 to permit a somewhat free ow of air or fluid or both between the core and the casing I3.A The fissure 25, aside from affording a capillary communication between the sets A and B of comb cuts, has the further function of serving to draw fluid from the vent 22 into the expansion chambers. Should a condition exist wherein fiuid overflows into the vent 22, such overflow is attracted back into .the expansion chambers for communication to the pen nib in writing or to the reservoir for storage. Providing such a capillary fissure 25 prevents overilow in the vent '22 from escaping through the open end thereof to blot the writing surface.

Referring now more particularly to Figs. 9 and 10, an extension 28 may preferably be formed integrally with the core I1 on the inner end thereof, the extension being of reduced cross section and having a groove 29 extending longitudinally on a peripheral portion thereof. The extension is directed upwardly to contact with a wall of the fluid reservoir II into which it extends. The groove 29 is preferably of capillary dimensions and is coextensive with the fissure 2l in the main body portion of the core. The. extension is employed in one position of the fountain pen to drain the fluid from the fluid feeding means back into the reservoir and is also employed to direct, by capillary attraction, fluid from the reservoir to the feeding means in the outer portion of the fountain pen.

While but a single embodiment of this invention is herein shown and described, it is tobe understood that various modifications thereof may be apparent to those skilled in the art without departing from the spirit and scope of this invention and, therefore, the same is only to be limited by the scope of the prior art and the appended claims.

We claim:

l. Ina fountain pen, a writing uid reservoir, a pen section' extending from one end thereof comprising a shell having a pen nib supporting portion, a core housed in said shell, said shell having a fis-sure therethrough on the pen'nib supporting surface thereof and said core having a fissure of capillary dimensions on the periphery thereof communicating with said reservoir and with said shell ssure for-directing uid from said reservoir to the pen nib, a capillary channel and capillary chambers in said pen section for holding the fluid in excess of the amount necessary for supplying said ssures, and an airpassage in said core in communication with said reservoir and with said capillary channel, said channel having communication with said fissures and said capillary chambers whereby said air passage ls sealed when said channel is supplied with fluid, and air is admitted to said air passage when the seal of said channel is broken to replace uid in said reservoir for the further supply of fluid therefrom to said fissures. y

2. In a fountain pen, a writing fluid reservoir, a pen section extending from one end thereof comprising a shell having a pen nib supporting portion, a core housed in said shell, said shell having a fissure therethrough on the pen nib supporting surface thereof and said core having a fissure of capillary dimensions on the periphery thereof communicating with said reservoir and with said shell fissure for directing fluid from said reservoir to the pen nib, a capillary groove and capillary chambers disposed peripherally of said core for holding the fluid in excess of the amount necessary for supplying said iissures, and an air passage in said core in communication with said reservoir and with said capillary groove, said groove having communication with said fissures and said capillary chambers whereby said air passage is vsealed when said groove is supplied with uid, and air is admitted to said air passage when the seal4 of said -shell ssure for directing fluid from said reservoir to the pen nib, said core being of reduced cross section over an internal peripheral portion thereof providing an undercut of capillary dimensions -with respect to the bore of said shell, capillary and air is admitted to said air passage when the seal of said undercut is broken to replace fluid in said reservoir for the further supply of fluid therefrom to said fissures.

4. In a fountain pen, a writing fluid reservoir, a pen section extending `from one end thereof comprising a shell having a pen nib supporting portion, a core housed in said shell, said shell having 'a ssure therethrough on the pen nib supporting surface thereof and said core having a fissure on the periphery thereof communicating with said reservoir and in registratiouwith said shell fissure for directing fluid from said reservoir to the pen nib, capillary chambers disposed peripheraliy of said core over an intermediate portion thereof, said core being of reduced cross section adjacent one end of said capillary chambers to provide an undercut of capillary dimensions with respect to the bore of said shell, said a passage extending for communication with 'said capillary chambers, and a longitudinally extending air passage in said Vcore in communication with said reservoir and with said under'- cut, said undercut having communication with said fissures and with said capillary chambers whereby said air passage is sealed when said undercut is supplied with fluid, and air is admitted to said air passage when the seal of said undercut is broken to replace fluid in said reservoir for the further supply of iiuid therefrom to said fissures. d

5. In a fountain pen, a writing fluid reservoir, a pen section extending from one end thereof comprising a shell having 'a pen nib supporting portion, a core housed in said shell, said shell having a fissure therethrough on the pen nib supporting surface thereof and said core having aflssure on the periphery thereof communicating with said reservoir and in registration with said shell fissure for directing fluid from said reservoir to the pen nib, transversely extending comb cuts of capillary dimensions disposed peripherally of said core over an intermediate portion thereof, said core being of reduced cross ,;sage -extendlng for communication with the 'comb cuts, and a longitudinally extending air chambers disposed peripherally of said core communicating with said fissures, and a longitudinally extending air passage in said core in communication with said reservoir and with said peripheral undercut, said undercut having communication with said fissures and with said cap- Aillar chambers wherebysaid air passage is sealed when said undercut is supplied with fluid,

passage in said core in communication with said reservoir and said undercut, said undercut having communication with said fissures and with said comb cuts 'whereby said air passage is 'sealed'when said undercut is supplied with uid, v

and air is admitted to said air passage when the seal of said undercut is broken to replace fluid in said reservoir for the further supply of uid therefrom to said fissures.

mediateportion of reduced cross section with the end portions engaging the -bore of said shell,

- said shell having a fissure therethrough on the pen-nib supporting surface thereof and said core having a fissure on the periphery thereof communicating with said reservoir and with said shell fissure for directing fluid from said reservoir to the pen nib, a shoulder at one end of the portion of said core of reduced cross section forming a channel of capillary dimensions with respect to the bore of said shell, capillary chambers disposed peripherally of the portion of reduced cross section of said core, said core having an aperture in communication between the atmosphere at the writing point end of said pen section and'said capillary chambers, and an air passage in said core communicating with said reservoir and with said capillary channel, said channel having communication with said iissures and with said capillary chambers whereby said air passage is sealed when said channel is supplied with uid, and air is admitted to said air passage when the seal ofsaid channel is broken to replace fluid in said reservoir for the further supply of uid therefrom to said fissures.

7. In a fountain pen, a writing fluid reservoir, a pen section extending' from one end thereof comprising an open-ended shell having a pen nib supporting portion, a .core having an intermediate portion of reduced cross section with the end portions engaging the bore of saidv shell, said shell having a fissure therethrough on the pen nib supporting surface thereof and said corq having a fissure on the periphery thereof communicating with said reservoir and with said shell ssure for directing fluid from said reservoir to the pen nib, a capillary channel and transversely extending comb cuts of capillary dimensions disposed peripherally of the portion of reduced cross sectionf of said core, said core having an aperture communicating with the atmosphere at the vwriting point end of said pen section and with the comb cuts intermediate the ends thereof, and a longitudinally extending air passage in said core communicating with said reservoir and with said capillary channel, said channel having communicationl with said ssures and with said comb cuts wherebyv said air 'passage is sealed when said channel is Supplied with iiuid, and air is admitted to said air passage when the seal of said channel is broken to revshell fissure for directing fluid from said. resersage when the seal of said channel is broken to replace fluid in said reservoir for the further supply of iiuid therefrom to said fissures.

9. vIn a. fountain pen, a writing fluid reservoir, a pen section extending from one end thereof `comprising an open-ended shell having a pen nib supporting portion, a core having an intermediate portion of reduced cross section with the end portions engaging the .bore of said shell, said shell having a fissure therethrough on the pen nib supporting surface thereof and said core having a ssure on the periphery thereof communieating with' said reservoir and with said shell fissure for directing uid from said reservoir to the pen nib, transversely extending comb cuts of capillary dimensions disposed peripherally of said reduced cross section ofsaid core, said core having an axial aperture communicating with the atmosphere at the writing point end of safid pen section and with a passage extending transversely of the axis of said core for communication with the comb cuts adjacent the other end thereof, and a longitudinally extending air passage in saidcore communicating at one end thereof with said reservoir.I and at the other end thereof with a peripheral undercut in said core at the shoulder formed by the junction of the portion of reduced cross section thereof, said undercut having communication with said `fissures and with said comb outs whereby said air passage is 'sealed when said undercut is supplied with fluid and air is admitted to said air passage when the `seal of said undercut is broken to replace fluid in said reservoir for the further supply of iuid therefromtosaid fissures.

10. In a fountain pen, a Writing fluid reservoir, a pen section extending from one endthereof comprising a shell having a pen nib supporting portion, a core housed in said shell, said shell having a, fissure therethrough over a portion 'of the pen `nib supporting surface thereof and said core having a Ifissure of capillary dimensions on the periphery thereof communicating with said y core having an aperture communicating with the v atmosphere and with said capillary chambers, an

air passage in said core communicating at one end thereof with said reservoir, and sealing means on said core for the other end of said air passage, said sealing means being operative to seal said air' passage when the supply of uid from the reservoir is in excess of the amount required 4by said fissures, and being operative to permit av passage of air to said air passage when the supply of |fluid from said reservoir to said fissures is in the amount required by said fissures to replace fluid in said reservoir for the further voir to the pen nib, capillary chambers disposed peripherally of said core over the portion thereof of reduced cross section, said core having an aperture communicating with the atmosphere at 4the writing point 'end of said pen section and with said capillary chambers, a shoulder adja 'cent one end of said reduced portion forming a capillary groove with respect to said shell, and an air passage in said core communicating with said reservoir and with said capillary groove, said groove having communication with said iissures and with said chambers whereby said air passage is sealed when said channel is supplied with fluid, and air is admitted to said air passupply of 'uuid to said iissures.

1-1. In a fountain pen, a wniting fluid reservoir, a pen section extending from one end thereof for supporting a pen nib, said pen section comprising a shell and a core housed 'in said shell, said core having a ssure of capillary dimensions communicating between said reservoir and said pen nib for supplying writing fluid thereto, a capillary mitted to said air passage when the seal of said channel is broken to replace fluid in said reservoir for the l further supply of fluid therefrom to said issure.

1'2. In a fountain pen, -a writing fluid reservoir, a pen section extending from one end thereof for supporting a pen nib, said pen section comprising a shell having a core housed therein, capillary chambers disposed peripherally of said core, a

ssure of capillary dimensions extending longitudinally of said core intersecting said capillary chambers and communicating between said reservoir and said pen nib for the supply of uid to a writing surface, and an airduct in said core communicating with said reservoir andv extending therefrom in the direction of the writing point end of said pen section, and sealing means between said air duct and said ssure and capillary chambers to govern the supply of Aair to said res-- ervoir for the control of fluid therefrom to said fissure.

13. In a fountain pen, a writing fluid reservoir,

` a pen section extending from one end thereof for supporting a pen nib, said pen section comprising a shell having va'core housed therein,

means for supplying writing iiuid from said reservoir to said pen nib, sets of capillary chambers disposed peripherally of said core,for receiving any excess of fluid from said supplying means, said sets being spaced by a channel of greater than capillary dimensions,- and an air vent communicating between the outside atmosphere and said channel.

- 14. In a fountain pen, a writing fluid reservoir, a pen section extending from one end thereof for supporting a pen nib, said pen section comprising a shell having a core housed therein,

` means for supplying writing fluid from said reserhaving an -intermediate portion of reduced cross t section, means for supplying writing fluid from said reservoir to said pen nib, spaced sets of capillary chambers disposed peripheraliy of the reduced portion of said core for receiving any excess of fluid from said supplying means, and an air vent extending internally through said core and communicating between the outside atmosphere and the space between said sets of capillary chambers.

16. In a fountain pen, a writing iiuid reservoir, a pen section extending from one end thereof for supporting a pen nib, said pen section comprising a shell having a. core housed therein, means for supplying writing uid from said reservoir to said pen nib, spaced sets-of capillary comb cuts disposed peripherally of said core for receiving any excess of iiuid from said supplying means, a. fissure in said core intersecting capillary comb cuts of both sets providing Acommunication therebetween, and an air vent communicating between the outside atmosphere and the space between said sets of capillary chambers.

' 17. In a fountain pen, a Writing iluid reservoir, a pen section extending from one end thereof for supporting a pen nib, said pen section comprislng a, shell having a core housed therein, capillary chambers disposed perlpherally of said core, a fissure extending longitudinally of said core intersecting said capillary chambers and oommunicating between said reservoir and said pen nib for the supply of uid to a writing surface, a reducedrextension on said core extending beyond the confines of said shelll into said reservoir, and a fissure in said extension coextensive with said core fissure for directing a supply of writing fluid from said reservoir to said core fissure during normal use in writing and for draining. said core fissure of fluid during normal condition of non-use.

18. In a fountain pen, a writing fluid reservoir, a pen section extending from one end thereof for supporting a, pen nib, said pen section comprising ashell of substantially uniform diameter internally thereof having a core housed therein, said core having an intermediate portion of reduced cross section, capillary chambers disposed peripherally of said core, over the reduced portion thereof, a fissure extending longitudinally of said core intersecting said capillary chambers and communicating between said reservoir and said pen nib for the supply of uid to a writing sur.- face, an air duct extending longitudinally over a peripheral portion of said core in communication with said reservoir, sealing means between said air duct and said issure and capillary chambers to govern the supply of air to said reservoir for the control of iiuid therefrom to'said ssure, and cut-away portions on each side of said air duct peripheraliy of said core intersecting said capillary chambers.

19. In a fountain pen, a writing fluid reservoir,

ing a shell having' a core housed therein, capillary chambers disposed peripheraliy of said core, av

fissure extending longitudinally of said core over a peripheral vportion thereof intersecting said capillary chambers and communicating between said reservoir and said pen nib for the supply of fluid to a writing surface, and an air duct disposed peripheraliy of said core in a spaced relation from said'ssure and capillary chambers communicating with said reservoir and extending therefrom in the direction of the writing point end of said pen section, and'means for establishing a controlled communication between said air duct and said fissure and capillary chambers.

LYNN P. MARTIN. HERMAN K. sTEMPEL. 

